a) Technical Field of the Invention
The present invention relates to a slat-actuating and positioning device for venetian blinds, and in particular, to a slat-actuating device employing a plurality sets of restriction cords for the mounting of the blind slats so as to firmly actuate (releasing or closing) the slats of the venetian blinds.
b) Description of the Prior Art
A conventional venetian blinds structure has been disclosed in ROC Utility Model Patent No. 81204926. As shown in FIGS. 6 and 7, there is a restriction cord 22 located in between two lateral main cords 21 of a pulling cord 20. The restriction cord 22 restricts the top and the bottom of the slat 30. At the center of the blind slat 30, a hole 31 is provided to allow the passage of a suspension cord 40 so as to actuate the upward and downward movement of the slat 30. In this structure, the replacement of blind slat 30 is very difficult and inconvenient With respect to mounting procedures. An improvement of this structure is shown in FIG. 7. In between two lateral main cords 21 of a pulling cord 20, a respective restriction cord 22 is provided to restrict the top and the bottom of the blind slat 30. In this structure, no hole is provided to the blind slat 30. However, the slat 30, at a position corresponding to one side of the main cord 21, is provided with a recessed positioning notch 32. At the lateral side of the slats, a plurality of holes are provided for the passage of a suspension cord 40. Thus, when the blind slats 30 and the bottom base seat 50 are actuated, the blind slats 30 and the bottom base seat 50 are lifted by force of the suspension cord 40. Thus, the blind slats 30 and the base seat 50 will be tilted and separated. As a result of the uneven force exerted in actuating the blind slats 30, the suspension cord 40 may be damaged. In addition, the combination of the blind slats 30 by pulling is separated and not in order.